Treating tank



Oct.V 9, 1.945. R. s. wl-:BsTE ETA;

TREATING TANK -2 sheets-sheet 1 n Filed Sept. 27,` 1944 OGL 9, 1945. R. s. wE'BsTl-:R ETAL 2,386,415

l 'TREATING TANK Filed Sept. 27', 1944 l 2 Sheets-Sheet 2 Patented Oct. 9, 1945 TREATING-TANK Roderick S. Webster, Evanston, Aand. vPhillip C.

Will, Oak Park, Ill., assignors to The Hydro- Blast Corporation l Claims.

I'Tl'iisfinvention relates to treating tanks and moreparticularly to apparatus for separating or classifying solid materials from a mixture `of liquids and soluble solids.

Various types of treating tanks have'been .used for settling and classifying solids carried by liquids, as Vfor example in the settling or classifying of sands from a slurry of sand and water.

'In the use of such apparatus ithas been difficult to .obtain accurate and economical settling` or classification due to agitation of the liquid in the tanks .resulting from flow therethrough. Such agitation tends vto produce eddy currentscausing uneven settling and classification.

The lideal situation in a tank of this character is one in whichow from ythe inlet to the outlet of the tank is'uniform throughout vthe full tank cross section. VUnder such .ow conditions very accurate and uniform settling or classification can Vbe produced. "It is, accordingly, oneofthe objects of the present invention to provide a treating tank in which flow conditions approach the ideal. Y.

Another object of the invention is to provide a treating tank in which the mixture of liquid and solids is .received in an entrance .chamber formed by a transverse partition in the tank.

'Still .another object is to provide .a treating tank in .which the mixture. entering vthe tank ows over a sloping plate on which .the kinetic energy of-.the owing mixture is largely dissipated.

A.further object of the invention is to provide a treating tank in which the entering mixture flowsfrom'an entrancechamber overan upwardly sloping inlet plate and a downwardly -sloping beach plate into the tank.

The aboveand other objects and advantages of the invention will be more readily apparent from vthe following description when readin connection with the accompanying drawings, in which:

Figure lis-alongitudinal section of a treating tank embodying the invention,

Figure 2 is a partial plan View, and

Figure 3 is a section on the line 3-3 of Figure 1.

The invention is illustrated in connectionwith an upflow type of liquid classifier, including a generally rectangular tank lIl having in its bottom a series of classifier cones Il to which Water is supplied through pipes I2. Heavy solids carried in suspension in the liquid in the tank will settle into the classifier cones and flow through openings I3 in the bottom thereof with a portion of the liquid from the tank. The lighter solids which cannot sink through the rising current of Water in the classifier cones will be carried out a Weir plate I4 at the disharge end of the tank. Thevweir plate I4 establishes the .desired liquid level 'in the tank as indicated bythe dotted line I5.

` The mixture of liquid and insoluble solids to be classified enters the tank through an .inlet pipe 'I6 terminating in a discharge end .sloping downwardly and inwardly into the tank. Apartition I'I extends across the tank inwardly of :the inlet .pipe and slopes upwardly at an acute angle to the vertical toward the inlet pipe, terminatingbelow fthe normal liquid level inthe tank. The partition forms an inlet chamber I8 into which the mixture of liquids and solids discharges and from which the mixture ows over the partition into .the main portion of the .,tank.

In order .to provide smooth and even .ow of liquids .into the .tank to minimize eddy currents and other flow disturbances, a beach plate l5 is provided connectedat its inner edge to the upper edge of the partition and sloping upwardly toward the inletpipe at an acute vangle to the vertical. The'beach plate .extends at its upper edge above the normal `liquid level in the tank `and is connected to an inlet plate v2| whichv slopes downward toward theinlet pipe atan acute angle to the horizontal. In operation mixture supplied to the inlet chamber I8 is highly agitated therein .to maintain the solidsin suspensionand flows over the inlet plate 2 I and beach plate I9 into the main portion of the tank.

We have found that the angles and locations of the 4beach plate land inlet rplate for proper results are quite critical. The beach plate, for example, must be so located that the liquid in the tank will normally extend-over its .lower end to provide a wedge shaped body of liquid. This plate, furthermore, must be at such an .angle that the solids will not drop .from the liquid on thesurface of the plate and .that themixture will not flow too rapidly down the plate'into the tank. When the angle and location of the plate are properly selected, mixture flowing over the upper edge thereof flows smoothly across the plate without dropping any solids and strikes the wedge shaped body of liquid overlying the lower 4 edge of the plate. At this point the kinetic energy in the flowing liquid is largely dissipated so that it moves smoothly into the main body of the liquid in the tank without creating eddy currents or other flow agitation. It will be noted that the existing level in the tank, and consequently the level above the lower edge of the beach plate,

will vary in accordance with the rate of flow into the tank, but this is desirable since a larger body of liquid on the beach plate is necessary to dissithe normal4 water. level in the tank is approxi` mately one and one-half inches above the lower edge of the4 beach plate.

The angle of the inlet plate 2l is also important' to produce a smooth, even flow. If this plate isv too nearly vertical the mixture from theinlet chamber i8 flows over it in uneven surges or pulses, while if it is too nearly horizontal lsolids tend to deposit on it, interfering with proper flow. We have found thatthe most satisfactory results are obtained when this plate lies at an angle of approximately 36 to the horizontal At thisangle no solids will deposit on the inletplate andthe mixture vfrom the'inlet .chamber ilows smoothly. over it onto the beach plate. f j Where the ow through the tank is relatively rapid there is' a'tendency to "create strong sur# face' currents from' the inlet toward the .outlet end of the tank which may `carry `over some of theA material it is desired to settleor classify. To avoid this a transverse baiileV 212 may be placed in'the tank as by suspending it from hooks 2,3,

hooking over the edges of the ltank.` The baille 2'2 is relatively narrow so that it'projects only slightly below the liquid levelin the tank. When this baffle is employed, it breaks; up anyl tendency toward direct surface currents and assists in ob taining the desired 'uniform ilow. across'the full section of the tank. With'the construction of thepresent invention flow of mixture to the tank is uniform with a minimum of eddy currents orother agitation of theliquid, so that accurate classification of solids can be obtained. While oneV embodmentof the inventiony has heen shown and described in detail, it will 'be understoodv that this is illustrative only and is not to be taken as a definition of the scope of the invention', reference being had for this 'purpose to the appended claims.

n What is claimed is:

1; In a treating tank for treating a mixture of liquid and insoluble solids, a mixture inlet pipe discharging downwardly and Vinwardly of the tank 'at one end thereof, a partition extending transversely' across the tank'inward of the inlet pipe, 'a beach plate connected' to the partition In a treating tank `for treating a mixture of liquid and insoluble solids, a mixture inlet pipe discharging downwardly and inwardly of the tank at one end thereof, a partition extending transversely across the tank inward of the inlet pipe, a beach plate connected to theV partition lying at an acute angle to the horizontal and sloping downward from said one end of the tank with its lower edge below the normal liquid level in the tank, and atransverse baffleplate in the tank spaced inward from the partition and beach plate and terminating at its lower edge slightly lbelow the normal liquid level in the tank.

3. In a treating tank for treating a mixture of liquid and insoluble solids, a mixture inlet pipe discharging downwardly and inwardly of the tank' atone end thereof, a transverse partition in Ltheltank inward of the inlet pipe and sloping downward at an acute angle to the Vertical away Yfrom rsaid one end and terminating at its upper edge below the normal liquid level in the tank, a beach plate secured at one edge to the upper edge of the partition and sloping upward therefrom at an acute angle to the horizontal vtowardV said one end of the tank,y and an inlet platel se-4 cured to the upper edge of' the beach plateafnd4 sloping downward rat anv acute angleV to the horizontal toward said one end of the tank. 4

4. In aV treating tank for treating a mixture of liquid and insoluble solids, a mixture inlet Vpipe discharging Adownwardly and inwardly of the tank at one end thereof', a transverse partition in the tank inward of the inlet pipe and sloping downward at an acute angle to the vertical away', from said one end and terminating at'its upper' edge below the normal liquid level in the tank, a beach plate secured at one edge 'to the upperI edge of the partition and sloping upward there-1 from at an acute angle to the horizontal toward said one end of the tank, an inlet plate secured to the upper edge of the beach Vplatel and sloping downward at 'an acute angle tothe' horizontal;

toward said one end of thetank, and a transverse baille in the tank inward of theA partition ter-` minating at its lower edge slightly below 'the' normal liquid level in theY tank.

5. In a treating tank for treating a mixture of therefrom at an angle of approximately 9 to the' horizontal toward said one end of the tank, and

an inlet plate secured to the upper edge of the beach plate and sloping 'downwardat' an angle ofapproximately 36 to the horizontal towardl 

